Introducing English Linguistics

Thematic structure
In traditional grammar, sentences are often divided into a subject and a
predicate. In the very simple sentence The boy walked the dog, The boy is the
subject and walked the dog the predicate. The notions “subject” and “pred-
icate” are related to syntax (the topic of the next chapter): how con-
stituents are ordered within a sentence or, more basically, a clause. The
above example is a main clause that is also a declarative sentence.
Elements in clauses, however, can be viewed from a different perspec-
tive, specifically in terms of how their placement in a clause contributes
to the flow of information in a text and helps connect one clause with
another. Viewing clauses from this perspective involves the study of their
thematic structure.
The study of thematic structure is rooted in work on functional sen-
tence perspective (FSP) conducted originally by Prague School linguists
such as Frantisek Dane
 (1974) and Jan Firbas (1992) and adapted for
English by the British linguist Michael A. K. Halliday (see Halliday and
Matthiessen 2004). The theory of FSP explains why speakers/writers pick
one word order over another – why, for instance, they would say or write